Tool for reservicing springs equipped with spring-covers



June 4, 1935. V w. F. EVISENHAUER TOOL FOR RESERVICING SPRINGS EQUIPPED WITH SPRING COVERS 0 Filed -June 20. 19 54 ;c .INl ENTORI I I {/4278}! F z'serrfieae f its ATTORNEY 10 tainin'g'riding comfort. One large-use of-s pring Patented June- 4,. a

. 9W?2.003308 a I; i TOOL Fon- RESERVICING srnmesn 7 est OFFICE F t j EQUIFPED WITH SPRING-C VERS Warren F. Eisenhauenpambridge, Mass assignor to Anderson Manufacturing Company; Gain-- bridge, Massi, a corporation ofMassachusetts .Applicationiune 2a, 1934, SerialNo. 1:31.556 p 11 Claims. (o1. ar- 105) 1 covers. Which requires servicing of the enclosed springs from time to time in orderto maintain a predetermined spring action isfound inthemb- 15 torl'car industry. F

.If the spring -cover dui t mailed by the car manufacturerthe. spring is serviced by thoroughly'covering each separate plate,; particularly over their contact areas, preferably with a graphite grease compound that acts asa stabil izer and packing after final assembly. If the springs are to be initially serviced and covered by the car owner then the plates of each spring are separated for receiving the stabilizing 'compound between them." Just beforeapplying the plie'dto the exposedsurfaces of the spring. The spring-cover holds this compound in' place and. keeps outdirt and-water, the latter; being very detrimental to satisfactory spring action. The bulk of present day spring-covers are metallic, al-.

though. flexiblematerials arestill in use to some extent,and,usually aqduclcor canvas lineris wrapped aboutthe packed spring before the cover 85 i applied. 1

1 During t e years that spring-covershave been used it has been found that certain conditions make. it advisable to re-service the spring. Reser'vicing maybe accomplished by removing the covering material .and; -re-packing. the-spring plates with the stabilizing compound orthe-plates may belrepacked thrbugh the cover and liner' without-:remgvalfrom the-springby the use of the service toollof thisinvention.

It is highly important that the greasingxcom-r pound for re-servicing be introduced in such a manner that it will reach the spring inside the liner and spread betweentheplates. Care must be taken. that. .the com pound is not spread merely between the linerand the cover for then its eflicacy is substantially nullified.

The principal object of theinvention is to provide a service tool-adapted to receive a fitting for; use with a pressure grease gun. enabling. any service station operative properly to re-service mulcovering materials more i? the compound is aptiplelleaf springs equipped with any type of springcover.- A further object of the invention is to provide a small, light re-servicing tool that may be easily manipulated as a handtool by an unskilled operator with wholly satisfactory results. .To the accomplishment of these objects and {such othersasinay hereinafter appear the invention comprises a hand tool having special features enablingtransmisSion of the greasing compound from thesource of supply directly upon and' between the plates of the spring to bere-.

serviced, hereinafter described and then particularlypointedcut in the appended claims,

The preferred form of the invention, together with certain modifications, is illustrated in, the i5 accompanying drawing, in which: 7

t Figure 1; .is-a view,,inside elevation, of a portion of a spring equipped with a cover the cover being broken away from one side and the service tool having 'its injectionhead entered through a hole in thecover and engaging the canvas liner; r

M Fig. .2 is a view similartotFig. 1 showing the canvaslliner pierced by the injection headcf the service tool;

Fig. 3, is servicetoolp I 3 v r Fig. 4 is an enlargedvviem'in' elevation, of the injection head of thel service tool; Fig. 5 is a.view similar to Fig. 4 but turned 90 to show the faceof the sheared threadandroot;

Fig. 6 is a view, inelevation, of a modified form of the service tool; p

Fig. 7 is a view, plan, of the tool shown in Fig. 6; and

Fig. 8 is a view, in elevation, like" Fig. 4 but showing the modifiedlbuttress thread before shearing to the shape shown in Fig. 4.

In the embodiment of the invention illustrated more particularly by Figs. 3,4 and 5 of the drawing the service tool comprises abody I0 having an enlargement'at oneend forming a threaded p 25 a view, in vertical, section, of the socket l2 for receiving and retaining. any standard greasinggun fitting. An' axial duct [4 leads from liner 20 (Figs. 1and12) that lies inside the springr cover 22 and, when the spring-cover is initially applied to the spring, is wrapped about the greased spring-plates 24. The spring-cover, if of metal, is provided with a hole 26 through which the injection head I6 is introduced. No hole is required in afabric cover.

The working end of the hollow injection head is virtually a self-threading screw, in the preferred form of Figs. 4 and 5 but a valuable feature which is also embodied in the modified form of Fig. 6 is a helical formation adapted easily to thread itself through the liner and provided, for the purpose of breaking a hole in the fabric'ywith a spur-like. terminal which obtains a grip on'the rough fabric to bite into or tear through it on rotating the tool while pressed firmly against the outer face of the liner and holding it taut (see Fig. 1). v

A simple and eflicient way to form a spurred thread is to start with the modified buttress thread, for strength, illustrated in Fig. 8, two. threads being sufiicient. The end thread 30 is sheared axially at 32 through its root 34 to the shelf of the second thread; The end thread is also sheared along the helical thread shelf with a diagonal cut thereacross as indicated by the dot and dash lines 35 on Fig. 8. All of the dotted line portion of the end thread shown in Fig. 8 is thus removed and the 'singlehelical turn 36 then remaining, formed in 'partby the original first thread and in part by the second, has a lineal, instead of the original blunt, edge and, of essential importance here, is provided with a spur-like corner 38 (Figs. 4 and 5) at the top of the axial 'shear 32. The downward and outward slope of the helical shear is shown by the corner line 40 in Fig.4. It is within the scope' of the invention, as will be recognized by those skilledin the art, to produce this'form'of the injection'head in other ways, for example, by die-casting in the desired shape. In this specification shear includes a facing formed by either cutting or pressure. l v

In the modified form of Figs. 6 and? in injection head "42 having the helicalturn 44 providing a terminal spur 46 is preserved, the differ-'- ence being that the tube forming the duct is itself twisted to a helix to enable the tool to grip the liner upon rotation while in contact therewith. A liner piercing end is formed by shearing through the tube at its free end, as clearly shown by Figs. 6 and 7, and this shear cut servesto produce a spur-like terminal i6.

Both forms embody the features of a hollow injection head having its, working end sheared to form a spur-like terminal for piercing the liner when the tool is rotated while engaged with the liner. This is one important feature and while the helical form behind the spur facilitates entry of the injection" head inside of the liner those skilled in the artmay, readily devise other forms which 'will'be operative and which fall within the-scope of this invention.

In both forms provision is made against injury to the spur-like end when the tool ,is laid on a bench. In the preferred form a collar 50 is provided of sufiicient diameter to preventthe, working end of the injection head from touching the bench. In the modified form the pointed end 46 is within the diameter of the helix, so that it may not contact the bench when the tool is laid on its-side.

In operation, the injection .headis entered through the hole 26 in a metal spring-cover and,

after forcing the liner 20 inward until it is taut, is

then rotated (clockwise for the right-hand screw form illustrated) until the corner 38 or point 46 as the case may be engages and tears through the fabric. The end of the injection head immediately passes through the hole thus made and the broken liner liesback of the helix as shown in'Fig. 2. A grease gun fitting having previously been screwed into the socket l2 the complementary fitting on the grease gun hose is placed thereover and'the grease may then be pumped directly against the spring-plates 24. All danger of forcing grease between the liner and springcover has been eliminated. After the re-servicing operation is completed and the tool has been removed the hole 26 in the spring-cover may be closed by a plug button.

vention also disclosed in the co-pending applicationof Warren F. Eisenhauer and Warren T. Ferguson Serial No. 733,972, filed-July 6,1934 as a continuation of their application Serial No; 685,566, filed August 17,1933, but because said subject-matter, while necessary to the disclosure of the'joint invention, is the sole invention of Eisenhauer, it is'claimedonly in this application.

The nature and scope 'of the inventionhaving been indicated and its preferred and other embodiments having been specifically described, that which is claimed as new, i

1. A service tool,- for re-servicing springs equipped with a spring-cover having a liner, comprising a'body, an injection head extending from one end of said body providing a helical formation'adapted to'enter a hole formed in the coverpermitting engagement of the liner and 35 functioning to thread itself through the liner upon rotating the 'tool,ja socket at the other end of the body adapted toretain a grease gun fitting, and said tool having a. continuous grease duct ,from said socket through said" injection head. i

I 2. A service tool according to claim 1 in which said injection head is provided with a spur-like terminal for biting into the liner and forming a hole through which the injection'head may be entered by its rotation. i

3. A service tool, for re-servicing springs equipped with a spring-cover having a liner, comprising a hollow body," a hollow injection head secured to one end of said body, said head 60 having at its working end athread-like helix terminating in a spur-like shoulder for thread ing the head through said liner, and a socket at the other end of said hollow body for receiving a grease gun fitting. i

4. A service tool, "for re-servic'ing springs equipped with a spring-cover having a liner, comprising a hollow body,'an injection head secured to one end of said body consisting of a tube of helical form having its'free end shaped to form a spur-like terminal for threading the head through said liner, and a socket at the other end of said hollow body for'rec'eivi'ng a grease gun fitting; P

5. In a service tool for the injection of a greasing compound within the lining of a lined spring-cover, a hollow injection head having its working end shaped to form a spur-like terminal for piercing the liner. i

6. In aservice' tool for the injection of a greas "ing compound within the lining of a lined spring-cover, a tubular injection head having at least one thread at its working end and said thread being sheared axially through its root and also having its root cut away from the top 15 the thread root.

of said shear along the thread shelfto its bottom-leaving an exposed section of the root;,

7. A service toolgas defined by claim 6 in which the said thread is a modified buttress having its upper face beveled outwardly to a lineal edge.

8. In a service tool for the injection of lubricant to theinterior of a lined spring-cover, a hollow screw for piercingithe spring-cover'liner consisting of at least one thread at its working end, saidthread being sheared axially through 9. In a service tool forthe injection of lubricant tothe interior of a lined spring-cover, a

a hollow body having an injection head and form- 7 ing a duct for the passage of lubricant therethrough, said injection head having at least one screw thread and said thread presenting a.

longitudinal shear: face at itsjend forming a piercing terminal at said end for biting into the spring-cover liner.

10. A service tool, for re-servicing springs aooavos comprising a body providing a duct, and having an injection head extending from one end of said body providing a helical formation adapted to enter ahole formedin theccver permitting engagement of the liner and functioning to thread itself through the liner upon rotating the tool.

1 1. A service tool, for re-servicing springs equipped with a spring-cover having a liner,

comprising a body providing a duct, and having an injection head extendingfrom one end of said body providing a helical formation adapted to enter a hole formed in the cover permitting engagement of the liner and functioning to thread equipped with a spring-cover having a liner,

itself through the liner upon rotating the tool,

said 'duct having one end at said injection-head and being adapted for connection with supplying means at its other end.

grease I '20 WARREN F. EISENHAUER. 

